Duke Energy ranks second in carbon emissions among U.S. power companies

Duke Energy (NYSE: DUK) produced the second-highest amount of carbon dioxide among the nation’s 100 largest utilities in 2012, behind only Ohio-based American Electric Power.

But it produced 45 percent more power than AEP, which was fifth in the nation for power produced, while Charlotte, N.C.-based Duke ranked first.

That's according to the 2014 Benchmarking Air Emissions report issued Wednesday. It tracks power production and emissions of carbon, sodium dioxide, nitrogen oxides and mercury for the 100 largest utilities in the nation.